I love the sanding blade idea. I've never seen that, but it is pretty cool.

I like how the speakers are coming together. Still anxious to hear how you plan on finishing them. Let me tell you that Bondo on a large surface is a hassle to do in one "mix". I learned that the hard way and had to scrape off some Bondo that I didn't put enough hardener in as I was trying to cover one whole side of my subwoofer with one "batch" of Bondo before it started drying.

Needless to say, I had to do the sides in 3 "batches" each. Should be super smooth, but I wonder how much I am gaining over the MDF surface alone.

But that is my build, too much details for me to put it in your build thread. Sorry.

this thread wouldn't belong if it didn't get side tracked. LOLMDF is pretty darn straight. Your really going to extremes, should look great. Damn stuff is tricky to work with. There is a product called dynaglass I used once , operative word is once. It was so hard when it dried I could hardly sand it. The speakers are only 9x20 so I am going to use very little filler ,mostly sand and check with a straight edge.

As for the finish , I think there will be a baffle board made of hardwood where the drivers are mounted and then possible some veneer down the middle of the sides with black paint the a bunch of coats of clear. Still not sure if I will chamfer the edges or round over or just leave them as hard edges.